I don’t know about you but where I live, it has been hot! And the forecast is for more of the same. Illness brought on by heat can range from mild to severe and can even be deadly. In fact, 2023 set a record for US heat-related deaths, with more than 2,300 people dying last summer related to the heat. Let’s talk about what you should know about heat illnesses and how you can protect yourself.
What is heat-related illness?
As the name implies, this refers to an illness caused by heat. Exposure to high temperatures and humidity, especially excessive heat or prolonged exposure, can cause a range of heat-related illnesses. This includes, in order of severity:
-
Heat rash – A prickly stinging skin irritation.
-
Heat cramps – Painful muscle cramps and spasms, which can happen during or after physical activity in high heat.
-
Heat exhaustion – A feeling of severe tiredness associated with heavy sweating, rapid breathing, rapid heartbeat, and a weak pulse. This can progress to heat stroke if not treated.
-
Heat stroke – A life threatening condition, in which your body temperature rises to 104°- 106°F within minutes.
How is temperature regulated in the body?
Your body normally regulates its temperature through a complex process. The part of your brain called the hypothalamus is the driver. When you get hot, the hypothalamus activates receptors in your skin and blood vessels and other organs to help get rid of heat. You start to sweat, and the evaporation of sweat from your skin produces a cooling effect. Your capillaries dilate, which brings blood closer to the skin surface to help release heat. These are just a couple of the things happening.
What causes body temperature regulation to go wrong?
-
High humidity or high heat index – The combination of heat and humidity can be a killer. When the humidity is high, it is harder for sweat to evaporate, which makes one important cooling mechanism much less effective. When the heat index is about 91°F, you should take precautions and be vigilant about heat illness.
-
Dehydration – If you are not drinking enough fluids, you may become dehydrated, which lessens your body’s ability to sweat and causes lower blood volume.
-
Drinking alcohol – Alcohol impairs temperature regulation in the body in several ways.
-
Inappropriate clothing – Wearing heavy clothing, dark clothing, or clothes that do not allow sweat to evaporate easily. This includes sports padding, police or fire uniforms, industrial protective equipment, and certain religious clothing.
What are the other risk factors for heat-related illness?
-
Young age – The body’s ability to regulate temperature may not be fully developed in young children. Children also produce more heat with activity than adults. Children and teens often don’t think to rest or drink fluids when they are having fun, even in the heat.
-
Old age – Adults over 65 may not regulate body temperature as efficiently as younger adults. They also are more likely to have illnesses or be on medications that increase their risk for heat-related illness.
-
Drugs – This can include illegal drugs and prescription drugs. Common prescription medications that cause problems include beta blockers, diuretics, antihistamines, anxiety medications, amphetamines, Parkinson’s medications, or antipsychotics. Illegal drugs that cause problems include cocaine and amphetamines.
-
Weight – Being overweight or obese can cause your body to retain more heat.
-
Sudden changes in temperature or in exertional level – If your body is not used to the heat, or not used to exercising or doing heavy or outdoor work, you’re more likely to have problems. Your body needs time to adjust to these changes.
-
Working conditions – If you work outside or in a hot and humid indoor environment.
-
Poor physical fitness – If you are used to exercising regularly, your body tends to be better at regulating temperature.
-
Medical illness – Particularly diabetes, kidney problems, some neurologic conditions, heart problems, and high blood pressure.
-
Pregnancy
Next week, we will talk more about this subject, including more specific symptoms and measures you should take to treat heat-related illnesses, and how to prevent them.
If you have any questions about heat-related illness, please log into your account and send us your question. We are here to help.
Dr. Anita Bennett MD – Health Tip Content Editor